From: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
To: stable@vger.kernel.org
Cc: Greg Kroah-Hartman <gregkh@linuxfoundation.org>,
	patches@lists.linux.dev,
	Zilin Guan <zilin@seu.edu.cn>,
	Zhang Yi <yi.zhang@huawei.com>,
	Baokun Li <libaokun1@huawei.com>,
	Theodore Tso <tytso@mit.edu>,
	stable@kernel.org
Subject: [PATCH 6.18 617/641] ext4: fix memory leak in ext4_ext_shift_extents()
Date: Tue, 24 Feb 2026 17:25:43 -0800
Message-ID: <20260225012403.459841436@linuxfoundation.org>
In-Reply-To: <20260225012348.915798704@linuxfoundation.org>
References: <20260225012348.915798704@linuxfoundation.org>
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6.18-stable review patch.  If anyone has any objections, please let me know.

------------------

From: Zilin Guan <zilin@seu.edu.cn>

commit ca81109d4a8f192dc1cbad4a1ee25246363c2833 upstream.

In ext4_ext_shift_extents(), if the extent is NULL in the while loop, the
function returns immediately without releasing the path obtained via
ext4_find_extent(), leading to a memory leak.

Fix this by jumping to the out label to ensure the path is properly
released.

Fixes: a18ed359bdddc ("ext4: always check ext4_ext_find_extent result")
Signed-off-by: Zilin Guan <zilin@seu.edu.cn>
Reviewed-by: Zhang Yi <yi.zhang@huawei.com>
Reviewed-by: Baokun Li <libaokun1@huawei.com>
Link: https://patch.msgid.link/20251225084800.905701-1-zilin@seu.edu.cn
Signed-off-by: Theodore Ts'o <tytso@mit.edu>
Cc: stable@kernel.org
Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org>
---
 fs/ext4/extents.c |    3 ++-
 1 file changed, 2 insertions(+), 1 deletion(-)

--- a/fs/ext4/extents.c
+++ b/fs/ext4/extents.c
@@ -5410,7 +5410,8 @@ again:
 		if (!extent) {
 			EXT4_ERROR_INODE(inode, "unexpected hole at %lu",
 					 (unsigned long) *iterator);
-			return -EFSCORRUPTED;
+			ret = -EFSCORRUPTED;
+			goto out;
 		}
 		if (SHIFT == SHIFT_LEFT && *iterator >
 		    le32_to_cpu(extent->ee_block)) {